It's every guitarist's and bass player's nightmare: During playing, the guitar falls down because the strab slips of the strap-pins. That's why Security Locks were invented. And nowadays there are several different systems on the market. In my opinon, this system is the best. The strap is secure and does not wobble.
The different to other systems is: you don't have to push on a button in order to loosen the lock, but you have to pull a little knob. While the pushing thing can also happen accidently, the pulling will never happen if you don't plan it.
It's also very easy to install it on the bass and everything fits great together. The whole thing is made of metal which makes it very stable!